As Fig. 10, but for models with two dust components with density-dependent abundances. Results are shown for the cloud model C with $A_{\mathrm{V}}^{\mathrm{ext}}=1\mathrm{mag}$ and density thresholds n₀= 10³−3.2 × 10⁴ cm⁻³, with symbols for higher n₀ values shifted to slightly higher y-axis positions. In frame d, τ(J) is calculated using the actual dust models and the spatially varying extinction curves. The vertical lines in frames d-e indicate the corresponding single-dust results from Fig. 10 for the first (cyan lines) and the second (magenta lines) of the dust components.